Medical physicists across the country are striking from today, the latest in a long line of health sector employees to take industrial action in recent months.
The physicists, who are part of the team that delivers radiation oncology treatment safely, are refusing to work outside the hours of 8am-4.30pm for the next 10 days.
Just six DHBs provide radiation oncology services, including the Southern District Health Board.
Medical, women's and children's health general manager Karin Drummond said the strike could affect the DHB's ability to provide some services, and might mean some treatments were delayed.
"We understand that this will be very worrying for some patients and their families/whanau.
"Our clinical teams are working hard to prioritise patients and minimise the impact of this industrial action.''
Patients with appointments should turn up as scheduled, as the SDHB would contact patients directly if it needed to reschedule an appointment.
"We thank everyone for their understanding as we manage this situation.''
APEX Union physicists national president Mark Ashburner said having to work outside normal times was a regular feature of life for the clinicians.
The workforce of around 75 physicists nationwide is covered by a collective agreement, but district health boards had not made any offer to settle a new contract, despite seven months of negotiations, he said.
Senior advocate David Munro said they were a critical workforce, and not working late would have an impact on patient scheduling.
Delaying a settlement would see New Zealand lose graduate medical physicists to overseas hospitals, Mr Munro said.
Meanwhile, the New Zealand Resident Doctors' Association, which is balloting members for a possible week-long strike after contract talks broke down last week, has called on Health Minister David Clark to step in to try to settle the dispute.
"This entire dispute has been on the watch of a Labour government and a Labour minister,'' Mr Munro, who is also senior advocate for the RDA, said.
"Members are wondering why he has not been involved.''
Dr Clark said ministers were not party to pay negotiations, and it was not appropriate for him to get involved in them.
The RDA has applied to the Employment Relations Authority for facilitation talks to be held, while DHBs have said they were ready to talk further with the union.
The RDA has staged four 48-hour strikes so far this year, causing thousands of operations to be postponed.
